Over time, iron-type golf clubs evolved from the difficult-to-hit blade-type irons to the more forgiving cavity-back designs. Despite improvements in club head performance, cavity-back irons still share many of the shortcomings associated with traditional blade-type irons. For example, relatively narrow soles of the blade-type and cavity-back irons tend to “dig in” the ground during a golf swing, which may reduce shot accuracy and overall distance.
Shot accuracy and distance are also affected by the depth of the center of gravity of the club head relative to its strike face. In most irons, the center of gravity is typically positioned near the strike face. This shallow center of gravity placement does not allow sufficient dynamic flexing of the shaft toward alignment with the club head's center of gravity on the downswing to loft and square the strike face at impact with the ball. Thus, shallow center of gravity placement makes it more difficult to get the golf ball in the air and may result in hook/slice tendencies.
Oversized iron-type club heads having wider soles were intended to address these problems. Some of these club heads have a hollow construction similar to hybrid or wood-type club heads. The wider soles of such club heads increase the center of gravity depth and reduce the “digging in” effect associated with the blade-type and cavity-back irons. However, due to swing-weight considerations, the degree to which the sole of an iron-type club may be widened is limited. The added weight associated with a wider sole may feel excessive to an average golfer, ultimately affecting the golfer's confidence and enjoyment of the golf club.
Additionally, the wider soles and non-traditional club shapes of the oversized irons may negatively affect the sound produced at impact. Acoustics play an important role in the golfer's confidence and enjoyment of the golf club. Although the club head may impact a ball at or near the center, or “sweet” spot, of the face, the golfer may associate unpleasant aural characteristics with an off-center hit, become discouraged, and lose confidence in the club head. The loss in confidence may result in decreased shot accuracy and distance.